A particular feature of some social networks, including Twitter, is that software programmes can act within them in a similar way to human beings – indeed, in some cases it may not be obvious whether you are communicating with a human being or a piece of software.

There has been a rapid increase in the amount of automated use of Twitter. I will give some examples of such use, and discuss some potential implications for Twitter data mining, and for security/privacy. My talk will include both some older results and results from some very recent data analysis.